M17: realtime FX mượt — MMCSS Pro Audio + HIGH_PRIORITY_CLASS (JuceFxLoop), GUI tick cadence động 30/200ms (guiBusy), worklet CAP 32->48, track FX gửi input NGAY như master

native_bridge/juce_fx/CMakeLists.txt

@@ -39,8 +39,8 @@ target_compile_definitions(juce_fx_bridge PRIVATE JUCE_PLUGINHOST_VST3=1)
 # M2 GUI thread: runDispatchLoopUntil cần modal loops được phép
 target_compile_definitions(juce_fx_bridge PRIVATE JUCE_MODAL_LOOPS_PERMITTED=1)
 if(WIN32)
-  # timeBeginPeriod (winmm) — như fx_vst_bridge
-  target_link_libraries(juce_fx_bridge PRIVATE winmm)
+  # timeBeginPeriod (winmm) + MMCSS AvSetMmThreadCharacteristics (avrt)
+  target_link_libraries(juce_fx_bridge PRIVATE winmm avrt)
 endif()
 
 # ── M1 selftest (editor API — KHÔNG ship): verify editor host trên instance

native_bridge/juce_fx/JuceFxEngine.cpp

@@ -378,6 +378,19 @@ bool JuceFxEngine::isEditorOpen(uint32_t slot) const {
     return impl_->editors[slot].open;
 }
 
+bool JuceFxEngine::guiBusy() const {
+    {
+        std::lock_guard<std::mutex> lk(impl_->queueMutex);
+        if (!impl_->editorQueue.empty()) return true;
+    }
+    {
+        std::lock_guard<std::mutex> lk(impl_->editorMutex);
+        for (const auto& se : impl_->editors)
+            if (se.open) return true;
+    }
+    return !impl_->retryOpens.empty();  // GUI-thread-only — chỉ GUI thread gọi
+}
+
 std::string JuceFxEngine::takeCapturedState(uint32_t slot) {
     std::lock_guard<std::mutex> lk(impl_->editorMutex);
     if (slot >= impl_->editors.size()) return {};

native_bridge/juce_fx/JuceFxEngine.h

@@ -78,6 +78,10 @@ public:
     // Thread-safe đọc: editor slot đang hiển thị (Show/Hide) không.
     bool isEditorVisible(uint32_t slot) const;
 
+    // GUI host: có việc editor cần tick nhanh không (queue lệnh chờ / editor
+    // đang mở / retry Open chờ). Gọi từ GUI thread (retryOpens GUI-thread-only).
+    bool guiBusy() const;
+
     void shutdown();
 
 private:

native_bridge/juce_fx/JuceFxGuiHost.cpp

@@ -568,13 +568,14 @@ void JuceFxGuiHost::guiMain() {
     // Thread này trở thành JUCE message thread.
     std::cerr << "[JuceFxGuiHost] guiMain start" << std::endl;
     juce::initialiseJuce_GUI();
-    std::cerr << "[JuceFxGuiHost] initialiseJuce_GUI ok" << std::endl;
+    std::cerr << "[JuceFxGuiHost] initialiseJuce_GUI ok" << std::endl;
     // Cadence inline (30ms busy / 200ms idle) — KHÔNG dùng juce::Timer: trên GUI thread riêng,
     // timer callback không bao giờ fire dù runDispatchLoopUntil pump liên tục
     // (test cho thấy 0 tick). tick() ở đây chạy trên chính message thread nên
     // pump + tạo/xoá Component an toàn.
     {
-        using clock = std::chrono::steady_clock;
+        using clock = std::chrono::steady_clock;
+        const auto fastMs = std::chrono::milliseconds(30);
         const auto slowMs = std::chrono::milliseconds(200);
         auto lastTick = clock::now();
         while (!quit_.load()) {
@@ -596,7 +597,11 @@ void JuceFxGuiHost::guiMain() {
                 impl_->guiCv.notify_all();
             }
             juce::MessageManager::getInstance()->runDispatchLoopUntil(10);
-            const auto now = clock::now();
+            const auto now = clock::now();
+            // Cadence động: có việc editor (queue/open/retry) → 30ms giữ
+            // anchor/reconcile phản hồi nhanh; idle (không editor) → 200ms —
+            // giảm wakeup + churn GUI thread BELOW_NORMAL khi chỉ chạy audio.
+            const auto curMs = engine_.guiBusy() ? fastMs : slowMs;
             if (now - lastTick >= curMs) {
                 tick();
                 lastTick = now;

native_bridge/juce_fx/JuceFxLoop.cpp

@@ -16,6 +16,7 @@
 #endif
 #include <windows.h>
 #include <mmsystem.h>
+#include <avrt.h>
 #endif
 
 #include <algorithm>
@@ -229,6 +230,18 @@ int run_juce_fx_loop(const std::string& jobPath, const std::string& shmName,
 #ifdef _WIN32
     timeBeginPeriod(1);
     SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_HIGHEST);
+    // MMCSS "Pro Audio": Windows đảm bảo quantum + ưu tiên cho thread này khi
+    // CPU cạnh tranh — chống spike deschedule (loopMax 430ms / 5756ms ở log).
+    // AvSetMmThreadCharacteristicsW (Avrt.lib). Process HIGH_PRIORITY_CLASS —
+    // không cần admin (REALTIME_PRIORITY_CLASS cần SeIncreaseBasePriorityPrivilege).
+    DWORD mmTaskIndex = 0;
+    HANDLE hMm = AvSetMmThreadCharacteristicsW(L"Pro Audio", &mmTaskIndex);
+    if (hMm) {
+        SetPriorityClass(GetCurrentProcess(), HIGH_PRIORITY_CLASS);
+        std::cerr << "[JuceFxLoop] MMCSS Pro Audio ok" << std::endl;
+    } else {
+        std::cerr << "[JuceFxLoop] MMCSS unavailable err=" << GetLastError() << std::endl;
+    }
 #endif
 
     // Engine: prepare graph (chain theo fx_chain). sr/block từ job; header là
@@ -501,6 +514,7 @@ int run_juce_fx_loop(const std::string& jobPath, const std::string& shmName,
     guiHost.stop();      // M2: đóng editor (GUI thread) + dừng GUI thread + join
     fxshm::closeShm(v);
 #ifdef _WIN32
+    if (hMm) AvRevertMmThreadCharacteristics(hMm);
     timeEndPeriod(1);
 #endif
     std::cerr << "[JuceFxLoop] exit processed=" << processed << std::endl;